diff --git a/lib/sequelize.js b/lib/sequelize.js
index 39f81c2b29a5..1ece97bddc3a 100755
--- a/lib/sequelize.js
+++ b/lib/sequelize.js
@@ -1095,9 +1095,14 @@ class Sequelize {
       type = dialectTypes[type.key].extend(type);
     }
 
-    if (type instanceof DataTypes.ARRAY && dialectTypes[type.type.key]) {
-      type.type = dialectTypes[type.type.key].extend(type.type);
+    if (type instanceof DataTypes.ARRAY) {
+      if (!type.type) {
+        throw new Error('ARRAY is missing type definition for its values.');
+      } else if (dialectTypes[type.type.key]) {
+        type.type = dialectTypes[type.type.key].extend(type.type);
+      }
     }
+
     return type;
   }
 
diff --git a/test/integration/sequelize.test.js b/test/integration/sequelize.test.js
index 9e98ebd132d1..3ddabb937aa1 100755
--- a/test/integration/sequelize.test.js
+++ b/test/integration/sequelize.test.js
@@ -1205,6 +1205,16 @@ describe(Support.getTestDialectTeaser('Sequelize'), () => {
     });
   });
 
+  describe('define', () => {
+    it('raises an error if no values are defined', function() {
+      expect(() => {
+        this.sequelize.define('omnomnom', {
+          bla: { type: DataTypes.ARRAY }
+        });
+      }).to.throw(Error, 'ARRAY is missing type definition for its values.');
+    });
+  });
+
   describe('define', () => {
     [
       { type: DataTypes.ENUM, values: ['scheduled', 'active', 'finished']},